Just the fact that they exist can tell us a lot about conditions of the very early universe, there was a time when we though galaxies would take much longer than 300 million years to form. So, any theory about the conditions of the early universe needs to allow for large, complex features such as these galaxies to form. I would think spectroscopy would also be able to tell you the ratios of elements that exist in those early galaxies, though I wouldn't expect any surprises there it's still worth taking a look.

I'm no astronomer; if I can come up with a couple thoughts I'm sure someone in the field would be able to dream up a dozen more.

No problem. In cosmology it's perfectly acceptable to just invent some new theory to explain that away even if that new theory has no basis for existing other than the insistance that the big bang happened exactly 13.75billion years ago.

If they're barking up the wrong tree then at some point the mess of explanations will be crazy enough and someone will be smart enough to provide a simpler and better explanation and the accepted theory will change.

You know, like has happened over and over again in the past. The heliocentric model replacing the geocentric one. Caloric theory replacing phlogiston theory. And so on.

In replying to that sequence of posts you also forgot to add that slashdot is forever populated by anonymous cowards who *always* know that the current widely accepted theory for *any* scientific discipline is wrong and that whatever arbitrary replacement is eventually dreamed up (I don't think they ever understand what "evidence based" means) for it will also be wrong.

You can see the frequency shift, frequency distribution, and with the right equipment you can see the chemical composition. From this information you can determine the elemental composition of the early universe. This can be tested to see how the generations of stars evolved. This is important to us because the original universe was mostly hydrogen, a little helium, and tiny amounts of deuterium and lithium. Lithium and deuterium get burned up quick in stars so we don't see much of it in later generations.

What is your point exactly? Do you have anything of substance to contribute other than butthurt that people are out there tackling complex problems and you don't like that, strangely enough, determining the nature of the Universe isn't as simple as looking inside your lunchbox?

It's not too surprising that Hubble is hitting the upper reaches of its capabilities but this peering back towards the beginning is nothing short of fascinating. With so many other 'younger' galaxies potentially out there and currently hidden from sight is motivation to keep this research up and get JWST up and running.

Hopefully the James Webb Space Telescope will not get way off track in budget and schedule again (cautiously optimistic), slated for 2018 launch currently but in any case this is another example of the more we find out, the more we realize we don't know.

I wouldn't say the upper reaches of its capabilities, because it is limited by the age of the universe and the speed of light. 13.3 out of an estimated 13.6 Billion is pretty damned capable, and it could possibly be more if they spend more than 100 hours on the same spot.

We have the hugely huge deep field visible light, and now a deep field in IR. Perhaps it would be good to point out the reason for enthusiasm, since IR seems better at seeing back in time, and JWST is tuned for IR. Aside from the larger

Current theories predict we won't be able to see much father back than 13.3 billion years because of the "cosmic dark ages".

Before decoupling occurs most of the photons in the universe are interacting with electrons and protons in the photon–baryon fluid. The universe is opaque or "foggy" as a result. There is light but not light we could observe through telescopes. The baryonic matter in the universe consisted of ionized plasma, and it only became neutral when it gained free electrons during "recombination," thereby releasing the photons creating the CMB. When the photons were released (or decoupled) the universe became transparent. At this point the only radiation emitted is the 21 cm spin line of neutral hydrogen. There is currently an observational effort underway to detect this faint radiation, as it is in principle an even more powerful tool than the cosmic microwave background for studying the early universe. The Dark Ages are currently thought to have lasted between 150 million to 800 million years after the Big Bang. The recent (October 2010) discovery of UDFy-38135539, the first observed galaxy to have existed during the following reionization epoch, gives us a window into these times. The galaxy earliest in this period observed and thus also the most distant galaxy ever observed is currently on the record of Leiden University's Richard J. Bouwens and Garth D. Illingsworth from UC Observatories/Lick Observatory. They found the galaxy UDFj-39546284 to be at a time some 480 million years after the Big Bang or about halfway through the Cosmic Dark Ages at a distance of about 13.2 billion light-years.

I love seeing images like these. I wish some clever astronomer or graphics guru would make a 'flip book' type of image (think those old layered plastic anatomy pictures in encyclopedias) where each layer contains the galaxies at a certain distance.

That way you could see the evolution, or a qasi-3d image of what hubble is seeing.

Just think about it... these galaxies have been around for billions of years longer than ours. That means that any planets kicking around in there are going to have had billions of years longer to evolve than our little blue planet.

You apparently don't realize that the oldest known star in our galaxy is 13.2 Gy old (implying that our galaxy is at least that old).

Oh my god, you're right, these pictures must be absolutely useless. Quick, call NASA and tell them to turn off Hubble immediately before any more money is wasted!

All that we have, is an area to look at with our next next gen scope.

So what's different about the next next gen scope that means we won't just be getting a smaller area to look at with the next next next gen scope? Or has it got the "useful scientific information" module that they forgot to put in Hubble?

If that was true, the light would take a lot longer than 13 billion light years to reach us, because space would have expanded so much in the intervening time. They must have been closer than 13bly then, and further than 13bly now.

I have no idea if this is true or not, but when space expands, would the light occupying it stretch out too at the same pace? If that were the case, the expansion of space wouldn't add to the amount of time the light would take to get between two points.

The light does stretch out, which (I think) contributes to, but is not solely responsible for, red shift. But, the space through which it has yet to travel will continue to stretch - so travel time is still increased. Of course this is all subject to reference frames and relativity and all other kinds of craziness - as far as the light itself is concerned, no time has passed *head asplode*.

If we were separated (at time of sending) by one light year in a rapidly expanding universe, and I shone a laser at you

Astronomer: Isaac, guess what? First: We've discovered time travel. Second: Our telescopes can now see all the way back to 300 million years since the, uh, beginning of, uh, all that exists. Aren't you impressed?

Isaac: What a stupendous lie and intrigue to greet this fine, rotund moon! Let me process that on its face. First: Light has a velocity finite after all, and either this velocity is slower than I surmised or the creation is larger than I dared